Heat pipe structure

ABSTRACT

A heat pipe structure includes a first tubular body and a second tubular body. The first tubular body has a first chamber and a working fluid. A first capillary structure is disposed on outer circumference of the second tubular body. The second tubular body is disposed in the first chamber and has a second chamber. In the heat pipe structure, the vapor-phase working fluid flows within the first chamber, while the liquid-phase working fluid flows within the second chamber in separation from the vapor-phase working fluid. Accordingly, the impedance against the vapor is greatly reduced and the heat transfer efficiency is greatly enhanced to achieve excellent heat dissipation effect.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a heat pipe structure, andmore particularly to an improved heat pipe structure having multiplechambers, whereby the vapor-phase working fluid and the liquid-phaseworking fluid independently separately flow within different chambers totransfer heat. Accordingly, the heat transfer effect is greatly enhancedto achieve better heat dissipation effect.

2. Description of the Related Art

Following the continuous development of scientific and technicalindustries, the operation speed and performance of all kinds ofelectronic components have been continuously enhanced. In the meantime,the waste heat generated by the electronic products has become higherand higher. In the conventional heat dissipation devices, heat pipe is asimple but very effective heat dissipation means. The heat pipe canquickly transfer a large amount of heat via latent heat. The heat pipehas the advantages of uniform distribution of temperature, simplestructure, small size, light weight, no external action force, longlifetime, multiuse, etc. Therefore, different kinds of heat pipes havebeen widely applied in various fields for dissipating heat.

The heat pipe has an evaporation end and a condensation end and aninternal vacuumed chamber in which a working fluid is filled. Theworking fluid relatively has a lower boiling point due to the vacuumedstate of the chamber. The heat is transferred via the latent heat bymeans of phase change between liquid phase and vapor phase of theworking fluid. At the evaporation end, the working fluid carries away alarge amount of heat from a heat source via latent heat. The vapor isfull in the vacuumed chamber and is condensed into a liquid at thecondensation end to release heat. Through the capillary attraction ofthe capillary structure in the chamber, the liquid working fluid flowsback to the evaporation end to complete the phase change circulation.Accordingly, the vapor-liquid circulation is continued to effectivelytransfer the heat generated by the heat source to a remote end for heatexchange.

The conventional heat pipe generally has one single chamber and onesingle capillary structure so that the heat transfer efficiency of theconventional heat pipe is limited. Moreover, the liquid phase workingfluid and the vapor phase working fluid are mixed in the same sealedchamber. The backflow of the liquid will obstruct the vapor fromsmoothly flowing to deteriorate the heat transfer efficiency.Accordingly, the conventional heat pipe has the following shortcomings:

1. The heat transfer efficiency is poor.

2. The vapor-liquid circulation efficiency of the working fluid is poor.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide an improved heatpipe structure, which has better heat transfer performance and is ableto achieve excellent heat dissipation effect.

To achieve the above and other objects, the heat pipe structure of thepresent invention includes a first tubular body, a second tubular bodyand a first capillary structure.

The first tubular body has a first chamber and a working fluid. Thesecond tubular body is disposed in the first chamber and has a secondchamber.

The first capillary structure is disposed on outer circumference of thesecond tubular body.

At least one end of the heat pipe is in contact with a heat source forabsorbing the heat generated by the heat source. When the end of theheat pipe is heated, the working fluid in the heat pipe is evaporatedand converted from liquid phase into vapor phase. The vapor workingfluid then flows through second chamber to the other end of the heatpipe. After reaching the other end, the vapor working fluid is cooledand condensed into the liquid working fluid. The liquid working fluidthen flows through the first capillary structure back to the originalend of the heat pipe. Accordingly, the vapor-liquid circulation of theworking fluid is continuously performed to dissipate the heat.

In the heat pipe structure of the present invention, the vapor-phaseworking fluid and the liquid-phase working fluid independentlyseparately flow within different chambers to transfer heat. Accordingly,the heat transfer efficiency is greatly enhanced.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present inventionto achieve the above and other objects can be best understood byreferring to the following detailed description of the preferredembodiments and the accompanying drawings, wherein:

FIG. 1 is a longitudinal sectional view of a first embodiment of theheat pipe structure of the present invention;

FIG. 2A is a cross-sectional view of the first embodiment of the heatpipe structure of the present invention;

FIG. 2B is an enlarged view of circled area A of FIG. 2A;

FIG. 3 is a sectional view of the first embodiment of the heat pipestructure of the present invention;

FIG. 4 is a longitudinal sectional view of a second embodiment of theheat pipe structure of the present invention;

FIG. 5A is a cross-sectional view of the second embodiment of the heatpipe structure of the present invention;

FIG. 5B is an enlarged view of circled area B of FIG. 5A;

FIG. 6 is a sectional view of the second embodiment of the heat pipestructure of the present invention;

FIG. 7 is a longitudinal sectional view of a third embodiment of theheat pipe structure of the present invention;

FIG. 8A is a cross-sectional view of the third embodiment of the heatpipe structure of the present invention;

FIG. 8B is an enlarged view of circled area C of FIG. 8A; and

FIG. 9 is a sectional view of the third embodiment of the heat pipestructure of the present invention; and

FIG. 10 is a sectional view of a fourth embodiment of the heat pipestructure of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer to FIGS. 1, 2A and 2B. FIG. 1 is a longitudinal sectionalview of a first embodiment of the heat pipe structure of the presentinvention. FIG. 2A is a cross-sectional view of the first embodiment ofthe heat pipe structure of the present invention. FIG. 2B is an enlargedview of circled area A of FIG. 2A. According to the first embodiment,the heat pipe structure of the present invention includes a firsttubular body 10, a second tubular body 20 and a first capillarystructure 202.

The first tubular body 10 has a first chamber 101 and a working fluid 2.

The second tubular body 20 is disposed in the first chamber 101 and hasa second chamber 201.

The first capillary structure 202 is disposed on outer circumference ofthe second tubular body 20. The first capillary structure 202 isselected from a group consisting of a sintered powder body, a structureformed with multiple channels, a mesh body and a coating. In thisembodiment, the first capillary structure 202 is, but not limited to, asintered powder body for illustration purposes only.

The first tubular body 10 has an evaporation end 11 at one end and acondensation end 12 at the other end opposite to the evaporation end 11.

Please refer to FIG. 3. The evaporation end 11 is in contact with a heatsource 3 for absorbing the heat generated by the heat source 3 andtransferring the heat to the working fluid 2 in the first tubular body10. At this time, the working fluid 2 in the first tubular body 10 isevaporated and converted from the original liquid phase into vaporphase. Accordingly, a large amount of heat is transferred from theevaporation end 11 to the condensation end 12 with a heat sink 5. Thevapor working fluid 21 will enter the second chamber 201 to flow towardthe condensation end 12 opposite to the evaporation end 11. Afterflowing to the condensation end 12, the vapor working fluid 21 is cooledand condensed into the liquid phase. The liquid working fluid 22 thenflows through the first capillary structure 202 on the outercircumference of the second tubular body 20 back to the evaporation end11. Accordingly, the liquid phase-vapor phase circulation of the workingfluid 2 is continued in a separate state.

By means of the above arrangement, the heat transfer efficiency of theheat pipe structure can be greatly enhanced.

Please refer to FIGS. 4, 5A and 5B. FIG. 4 is a longitudinal sectionalview of a second embodiment of the heat pipe structure of the presentinvention. FIG. 5A is a cross-sectional view of the second embodiment ofthe heat pipe structure of the present invention. FIG. 5B is an enlargedview of circled area B of FIG. 5A. According to the second embodiment,the heat pipe structure of the present invention includes a firsttubular body 10, a second tubular body 20 and a second capillarystructure 102. The first tubular body 10 has a first chamber 101 and aworking fluid 2. The second capillary structure 102 is disposed in thefirst chamber 101. The second capillary structure 102 is selected from agroup consisting of a sintered powder body, a structure formed withmultiple channels, a mesh body and a coating. In this embodiment, thefirst capillary structure 202 is, but not limited to, a structure formedwith multiple channels for illustration purposes only.

The second tubular body 20 is disposed in the first chamber 101 and hasa second chamber 201. The first tubular body 10 has an evaporation end11 at one end and a condensation end 12 at the other end opposite to theevaporation end 11.

Please refer to FIG. 6. The evaporation end 11 is in contact with a heatsource 3 for absorbing the heat generated by the heat source 3 andtransferring the heat to the working fluid 2 in the first tubular body10. At this time, the working fluid 2 in the first tubular body 10 isevaporated and converted from the original liquid phase into vaporphase. Accordingly, a large amount of heat is transferred from theevaporation end 11 to the condensation end 12 with a heat sink 5. Thevapor working fluid 21 will enter the second chamber 201 to flow towardthe condensation end 12 opposite to the evaporation end 11. Afterflowing to the condensation end 12, the vapor working fluid 21 is cooledand condensed into the liquid phase. The liquid working fluid 22 thenflows through the second capillary structure 102 in the first chamber101 back to the evaporation end 11. Accordingly, the liquid phase-vaporphase circulation of the working fluid 2 is continued in a separatestate.

By means of the above arrangement, the heat transfer efficiency of theheat pipe structure can be greatly enhanced.

Please refer to FIGS. 7, 8A and 8B. FIG. 7 is a longitudinal sectionalview of a third embodiment of the heat pipe structure of the presentinvention. FIG. 8A is a cross-sectional view of the third embodiment ofthe heat pipe structure of the present invention. FIG. 8B is an enlargedview of circled area C of FIG. 8A. The third embodiment is substantiallyidentical to the first and second embodiments in component andrelationship between the components and thus will not be repeatedlydescribed hereinafter. The third embodiment is different from the firstand second embodiments in that both the first and second tubular bodies10, 20 respectively have the first and second capillary structures 202,102. The first capillary structure 202 is disposed on the outercircumference of the second tubular body 20, while the second capillarystructure 102 is disposed in the first chamber 101. The first and secondcapillary structures 202, 102 are selected from a group consisting ofsintered powder bodies, structures formed with multiple channels, meshbodies and coatings. In this embodiment, the first and second capillarystructures 202, 102 are, but not limited to, structures formed withmultiple channels for illustration purposes only.

Please refer to FIG. 9. The evaporation end 11 is in contact with a heatsource 3 for absorbing the heat generated by the heat source 3 andtransferring the heat to the working fluid 2 in the first tubular body10. At this time, the working fluid 2 in the first tubular body 10 isevaporated and converted from the original liquid phase into vaporphase. Accordingly, a large amount of heat is transferred from theevaporation end 11 to the condensation end 12 with a heat sink 5. Thevapor working fluid 21 will enter the second chamber 201 to flow towardthe condensation end 12 opposite to the evaporation end 11. Afterflowing to the condensation end 12, the vapor working fluid 21 is cooledand condensed into the liquid phase. The liquid working fluid 22 thenflows through the second capillary structure 102 in the first chamber101 and the first capillary structure 202 on the outer circumference ofthe second tubular body 20 back to the evaporation end 11. Accordingly,the liquid phase-vapor phase circulation of the working fluid 2 iscontinued in a separate state. By means of the above arrangement, theheat transfer efficiency of the heat pipe structure can be greatlyenhanced.

The working fluid is selected from a group consisting of pure water,coolant and acetone.

Finally, please refer to FIG. 10, which is a sectional view of a fourthembodiment of the heat pipe structure of the present invention. Thefourth embodiment is substantially identical to the first and secondembodiments in component and relationship between the components andthus will not be repeatedly described hereinafter. The fourth embodimentis different from the first and second embodiments in that the heat pipestructure further has a first section 41 and a second section 42disposed at two ends of the first tubular body 10 respectively. Thefirst and second sections 41, 42 communicate with the first and secondchambers 101, 201. The evaporation end 11 is attached to a heat source 3for transferring the heat. After the working fluid 2 is evaporated andconverted from liquid phase into vapor phase, a large amount of heat istransferred from the evaporation end 11 to the condensation end 12 witha heat sink 5. The vapor working fluid 21 will enter the second chamber201 to flow toward the condensation end 12 opposite to the evaporationend 11. At this time, the vapor working fluid 21 is cooled and condensedinto the liquid phase at the condensation end 12.

The liquid working fluid 22 then flows through the first capillarystructure 202 on the outer circumference of the second tubular body 20or the second capillary structure 102 in the first chamber 101 or boththe first and second capillary structures 202, 102 back to theevaporation end 11. Accordingly, the liquid phase-vapor phasecirculation of the working fluid 2 is continued in a separate state. Bymeans of the above arrangement, the heat transfer efficiency of the heatpipe structure can be greatly enhanced.

According to the aforesaid, in comparison with the conventional heatpipe, the present invention has the following advantages:

1. The heat transfer efficiency is increased.

2. The vapor-liquid circulation efficiency of the working fluid isbetter.

The above embodiments are only used to illustrate the present invention,not intended to limit the scope thereof. It is understood that manychanges and modifications of the above embodiments can be made withoutdeparting from the spirit of the present invention. The scope of thepresent invention is limited only by the appended claims.

What is claimed is:
 1. A heat pipe structure comprising: a first tubularbody having a first chamber and a working fluid; a second tubular bodydisposed in the first chamber and having a second chamber; and a firstcapillary structure disposed on outer circumference of the secondtubular body.
 2. The heat pipe structure as claimed in claim 1, whereina second capillary structure is disposed in the first chamber.
 3. Theheat pipe structure as claimed in claim 1, wherein the first tubularbody has an evaporation end at one end for contacting at least one heatsource and a condensation end at the other end opposite to theevaporation end.
 4. The heat pipe structure as claimed in claim 1,wherein the first capillary structure is selected from a groupconsisting of a sintered powder body, a structure formed with multiplechannels, a mesh body and a coating.
 5. The heat pipe structure asclaimed in claim 2, wherein the second capillary structure is selectedfrom a group consisting of a sintered
 6. The heat pipe structure asclaimed in claim 1, wherein the working fluid is selected from a groupconsisting of pure water, coolant and acetone.
 7. The heat pipestructure as claimed in claim 1, further comprising a first section anda second section disposed at two ends of the first tubular bodyrespectively, the first and second sections communicating with the firstand second chambers.